Hayden Smith, the Saracens lock, insists he has no regrets about pursuing his lifelong dream to play American Footballin the NFL even though his spell with the New York Jets lasted just 18 months.

Smith became the first professional rugby player to play in the NFL when he made five appearances for the Jets last season as a tight-end. He was released from the 53-strong roster after this year‘s pre-season in August.

And after an unsuccessful trial with Tampa Bay, he decided to return to rugby union and rejoined Saracens last week.

The contrasting emphasis on conditioning work between the two codes means that the 28-year-old US Eagles forward is likely to require a month-long intensive conditioning programme at Saracens before he can feature again for the club he first joined in 2008.

Smith, who was born in Sydney, admits the manner of his departure from the NFL after such a short spell was a frustrating. Yet he believes the experience was a life-changing one that will also benefit his rugby career.

“It is an amazing journey to have been a part of and you just take life experience from it,” said Smith, who left Australia when he was 18 and moved to the US to take up a basketball scholarship.

“It took a lot of work and wasn’t easy and I grew as a person by taking myself outside my comfort zone. American Football is about short bursts of speed and power. The guys are bigger but then they don’t have to have the endurance that rugby players do.

“So, having come back, one of the things I need to work on is getting my conditioning back to where it needs to be to play rugby again.

“You spend more time in the gym and then sprint training and body control. It is key to be able to change direction quickly without breaking stride.

“I did get a little bigger, stronger and faster as a result of the changes in my body and I hope to be able to keep some of those elements coming back to rugby.”

Even if Smith’s NFL experiment proved short-lived, there is little doubting the size of his achievement in just making the initial cut.

He says his NFL team-mates thought he was crazy for trying to make it in a sport having never played it before, but his decision to install an espresso machine in his locker because he did not like the club’s filter coffee soon helped to break the ice.

“I was definitely a bit of a novelty because they are not used to foreign players,” Smith added. “Coming in and not having played the game before was a huge task. People work their whole lives playing the sport to get to that stage.

“The first thing you have to understand is the language they use and the little nuances of what is actually happening on the field. Only then can you start working on techniques. It is a long process before you can actually take to the field and contribute.

“It took me months to be able to coherently understand what was going on and that was after putting in 12 or 14-hour long days. The playbook would contain hundreds of plays and thousands of varieties. You only have a couple of seconds to react once we snap the ball.

“You are also dealing with some incredible athletes so it is a pretty tough environment.“ The reintegration to life in the Aviva Premiership will not just be about his conditioning.

His debut for the Jets in October 2012 was in front of a crowd 85,000 at the MetLife Stadium against the Miami Dolphins and his highlight was catching a first down against San Diego.

Everything from the intense media spotlight to the extravagant travel for away games proved to be a bewildering experience.

“The New York media is something in itself,” he added. “There was at least 50 reporters at practice every day and they conduct interviews with the players one-on-one in the locker room afterwards.

“It is hard to imagine that here at Saracens. You adapt to the situation. You focus on training and then if you do well or don’t do well, they will ask you about it afterwards. You just got on with it.”

The travel arrangements were on a slightly grander scale, too.

“We had a private plane and flew with a staff of 161 for every away game,” he added. “It was certainly done very well. They would bring the airport security to our indoor training ground and then go straight onto the bus and have a police motorcade take us straight to the runway where we would get on the plane.

“After the game we would clear airport security under the stadium and then we would go straight to the bus back to the runway and fly straight home. You’re playing a game in Miami and would be back home that night after the game. It was pretty cool.”

Life might not be as “Hollywood” back at Saracens, but he is thankful to have been given a second chance.

“I got a bit of stick last week but it is great to be back,” he added.

“Saracens were fantastic in allowing me the opportunity to play in the NFL and I am loving every minute of being back.”